The human immunodeficiency viruses (HIV) is a species of Lentivirus ( a subgroup of retrovirus) that causes HIV infection and over time acquired immunodeficiency syndrome (AIDS). AIDS is a condition in humans in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive. Without treatment, average survival time after infection with HIV is estimated to be 9 to 11 years, depending on the HIV subtype. However, due to treatment, the prevalence of AIDS has dropped significantly.
HIV can be divided into two major types, HIV type 1 (HIV-1) and HIV type 2 (HIV-2). The HIV-1 group M viruses predominate and are responsible for the AIDS pandemic with more than 90% of HIV/AIDS cases deriving from infection with HIV-1 group M.
Sepsis in HIV
Sepsis is a major cause of morbidity and mortality in patients with HIV.
In Western settings, sepsis accounts for 33-35% of intensive care unit (ICU) admissions in HIV/AIDS patients, and is associated with a high mortality. A study in a Ugandan ICU showed that HIV infected patients were twice as likely to die as non-infected patients. With sepsis being the lead cause of admission.
In tropical regions, patients with HIV have higher rates of bacterial bloodstream infections. Sepsis is characterised by the presence of an infection combined with a systemic injurious host response. HIV patients have been observed to have profoundly severe capillary leak.
Of interest, HIV infection affects several components of the immune system in similar ways as sepsis; including leukocyte responses, the complement system and the coagulation system.
Studies show that HIV co-infection enhances the pro-inflammatory response during sepsis.
In new infection alone, seroconversion alone can lead to organ failure.
GENERAL MANAGEMENT PRINCIPLES
Infection management should be similar for other patients with the exception of unique considerations below.
- In endemic areas, a high index of suspicion should be observed for HIV infection. Routine Counselling and Testing.
- If presenting with fevers, tepid sponging and oral/IV paracetamol are more than adequate. Avoid NSAIDs and Steroids.
- Aggressive fluid resuscitation beyond 1 litre should be supplemented by adding a vasopressor.
- The next one litre of IV fluids (crystalloids) may contain 1mg adrenaline and the drip titrated to keep a systolic blood pressure at or above 100mg or keep target Mean Arteriole Pressure more than 65, capillary refill time of less than 4 sec, urine output more than 0.5ml/kg/hour and lactate levels less than 2mmol (if lactate can be measured)
- Oral rehydration should be encouraged. Resuscitation is done with crystalloids. Colloids may be used such as albumin.
- Oxygenation if necessary should be supplemented with facemask oxygen to saturation above 91% and the respiratory rate monitored not to go above 35 per minute or the patient may require assisted breathing.
- Antimicrobial therapy includes cotrimoxazole prophylaxis and a high index of suspicion for other opportunistic infections such as tuberculosis, toxoplasmosis or Pneumocystis jurovecii pneumonia or cryptococcal meningitis.
- Consider early initiation of ARV therapy in the absence of TB according to the national guidelines. Consider Dolutegravir based regimens for rapid viral load suppression.
- Patients with severe illness will need a referral to a hospital with HDU or an ICU. Protection of health workers and other patients is paramount especially in cases with suspected TB.